Should the Teeth on your Chain Wheel be Sharp?
 

Hi guys,

Got a new bike not too long ago. When I had about 50 miles on it, I examined the chain rings. I noticed that the teeth are not uniformly sharp and triangular. Instead, many are dull, of slightly different sizes, etc. However, they are not bent.

My question is this: are the teeth on chain rings supposed to be nice and sharp triangles, of a uniform size, or is it O.K. that they look like mine do (dull, different heights, etc.)?

Thanks!

Yes, they are like that to aid shifting. If your bike only has 50 miles on it, what you are looking at are brand new chainrings. With that few miles there should be no discernible wear. You might want to check them again at 5000 miles.:)

Take a look at this page, which explains it all:
http://sheldonbrown.com/gloss_ra-e.html#ramp

The last Shimano crank I installed for my brother actually had info printed right on the ring basically stating that the weird parts were normal. Little arrows pointed them out. They must have had a few people complain.

When they become sharp triangles ... that's a good sign it's time to replace them.

Haha.

Haha. I have to say when I got my first "modern" road bike I was really confused about the rings. I'm used to non-ramped rings.